8-bit SAR ADC with 4/8-channel mux — what it is and where it fits
The Maxim Integrated MAX1110EAP+T is an 8-bit successive-approximation (SAR) ADC with an integrated input multiplexer and sample-and-hold, packaged in a 20-pin SSOP. It samples at 50k samples per second over an SPI serial interface, accepting either differential or single-ended inputs through a configurable 4- or 8-channel front-end. The analog and digital supply rails share a common 2.7 V to 5.5 V range, simplifying the power tree to a single regulated rail. This part is suited for industrial sensor acquisition, battery-monitoring systems, and portable instrumentation where 8-bit resolution is adequate and low pin-count serial readout is preferred.
50 ksps sampling — what it means for your measurement loop
At 50k samples per second, each conversion completes in 20 µs. That paces the SPI bus at roughly 1 MHz SCLK for a single 8-bit read. For a multiplexed scan of all eight channels, the aggregate throughput is about 6.25k conversions per second per channel — fast enough for temperature, pressure, or current-sense loops in motor drives and power supplies, but not for audio or vibration capture above a few hundred Hz per channel. The SAR architecture gives deterministic conversion time with no pipeline delay, so the sample timing is predictable cycle-to-cycle.
Input channel routing — differential vs single-ended
The input multiplexer can be configured as four differential pairs or eight single-ended channels. In differential mode you get common-mode rejection on each pair — useful when the sensor signal travels a few inches of PCB trace or a short cable. Single-ended mode doubles the channel count for grounded-reference signals like ratiometric bridge outputs or potentiometer feedback. The internal sample-and-hold captures the selected input before conversion, with a 1:1 S/H-to-ADC ratio meaning no dead cycle between acquisition and conversion.
Supply range and reference options
Both AVDD and DVDD operate from 2.7 V to 5.5 V, and they can be tied together for a single-supply layout. The reference can be driven externally or supplied from an internal bandgap.
Industrial temperature range and package
Rated for -40°C to 85°C, the MAX1110EAP+T covers industrial and extended-commercial environments — factory-floor data acquisition, outdoor telecom cabinets, and under-hood automotive auxiliary monitoring. The 20-SSOP package (5.30 mm body width) is a surface-mount footprint that suits dense mixed-signal boards.
Lifecycle and sourcing posture
The MAX1110EAP+T carries an active lifecycle status from Maxim Integrated (now part of Analog Devices). ROHS3 compliant. For production BOMs requiring a qualified second source, the part is available through independent distribution channels — quoted to order against an RFQ with pricing and availability confirmed at quote time.